The House passed "Kristen's Law," sending it to the Senate, which has passed a similar bill.
It is named for Kristen Coutu, who died in 2014 of a fentanyl overdose. She thought she was taking heroin.
The man who sold her the drugs was convicted of second-degree murder. Democratic Attorney General Peter Kilmartin's bill would make it easier to bring those charges and levy up to a lifelong sentence for those convicted.
Lawmakers added an amendment to clarify that the statute would apply to drug dealers, not to people who shared drugs with a victim.
Medical and community groups have argued the bill would punish mostly low-level drug dealers and addicts. They have said it would be detrimental to curbing the overdose epidemic.
On Wednesday, Kilmartin hit back, accusing the bill's opponents of driving a false narrative.
"It is clear that the opponents of this legislation are trying to use inflammatory language to invoke fear rather than having an honest conversation about the criminal justice system and what this bill actually accomplishes in comparison with current law," Kilmartin said.
The attorney general has argued prosecutors would target predatory traffickers. He said the legislation was amended to reflect that focus and to ensure fellow addicts would not be prosecuted for reporting overdoses.
Dr. Jody Rich and Dr. Traci Green, two Brown professors on the governor's overdose task force, wrote in response that the bill remained unnecessarily broad. They said they already have seen the "aftereffects of incarceration-based drug policies."
"We ask that you please listen to those of us who are working every single day to prevent and treat substance use disorder," they wrote, "and whose job it is literally to save lives."
The chambers have to pass each other's version before it goes to the governor.
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